Precursor compounds for atomic layer deposition (ald) and chemical vapor deposition (cvd) and ald/cvd process using the same

ABSTRACT

The present invention relates to precursor compounds, and more particularly to nonpyrophoric precursor compounds suitable for use in thin film deposition through atomic layer deposition (ALD) or chemical vapor deposition (CVD), and to an ALD/CVD process using the same.

BACKGROUND OF THE INVENTION 1. Technical Field

The present invention relates to novel precursor compounds, and moreparticularly to nonpyrophoric precursor compounds, which enables thedeposition of a thin film through atomic layer deposition (ALD) andchemical vapor deposition (CVD), and to an ALD/CVD process using thesame.

2. Description of the Related Art

A technique for manufacturing an Al₂O₃ thin film using an ALD/CVDprocess is regarded as important from the viewpoints of solving problemswith organic electronic devices, such as preventing corrosion of metalmaterials due to humidity and creating a moisture barrier, and may alsobe applied to intermediate insulators and to solar cell passivation.

The formation of an Al₂O₃ thin film requires a deposition process at alow deposition temperature, specifically, a temperature lower than roomtemperature, and TMA [Al(CH₃)₃] is mainly utilized as a precursor formanufacturing an Al₂O₃ thin film using an existing ALD/CVD process.Here, TMA has an ideal ALD thin film deposition rate, but is pyrophoric,which is undesirable. Thus, research is ongoing into safe precursors forthe manufacture of large volumes on an industrial scale.

As for studies with regard to a nonpyrophoric precursor compoundincluding aluminum (Al) as a trivalent transition metal of Group 13, amethod of preparing [Al(CH₃)₂(μ-O^(i)Pr)]2 (DMAI, ^(i)Pr=isopropyl) isdisclosed in the literature [Plasma-enhanced and thermal atomic layerdeposition of Al₂O₃ using dimethylaluminum isopropoxide,[Al(CH₃)₂(μ-O^(i)Pr)]₂, as an alternative aluminum precursor (I Vac.Sci. Technol. A, 2012, 30(2), 021505-1)], but is problematic because thedensity of the Al₂O₃ thin film is low after the ALD process.

Accordingly, there is a need to develop a precursor, which isstructurally stable and thus makes it possible to form a thin film in awide temperature range (ALD window) during ALD/CVD, by newly designingthe structure of a precursor compound, which is nonpyrophoric and hasthermal stability that prevents decomposition after vaporization, andhigh reactivity with a variety of oxidizing, nitriding or reducingagents.

CITATION LIST Patent Literature

Korean Patent No. 10-1787204 (Registration Date: Oct. 11, 2017)

SUMMARY OF THE INVENTION

Therefore, the present invention is intended to provide a novelprecursor compound suitable for use in an atomic layer deposition (ALD)process and a chemical vapor deposition (CVD) process, and a method ofmanufacturing a thin film through deposition of the precursor compound.

According to the present invention, the novel precursor compound is aheteroleptic precursor compound composed of transition metals of Groups12 and 13. Since an existing homoleptic precursor compound ispyrophoric, the precursor compound of the present invention may be usedin place thereof, and has thermal stability that prevents decompositionupon vaporization and high reactivity with various oxidizing agents.

Also, the precursor compound of the present invention is capable ofproviding aluminum oxide (Al₂O₃) through an atomic layer deposition(ALD) process and a chemical vapor deposition (CVD) process using ozone(O₃) or water (H₂O), has a wide processing temperature range (ALDwindow), enables realization of a stoichiometric metal oxide thin filmhaving high purity, and may exhibit superior step coverage.

However, the problems to be solved by the present invention are notlimited to the foregoing, and other problems not mentioned will beclearly understood by those skilled in the art from the followingdescription.

An aspect of the present invention provides a compound represented byChemical Formula 1 below.

In Chemical Formula 1, when M is a divalent transition metal of Group 12on the periodic table, n is 1; when M is a trivalent transition metal ofGroup 13 on the periodic table, n is 2; and R₁ to R₅ are hydrogen, asubstituted or unsubstituted C1 to C4 linear or branched alkyl group oran isomer thereof.

Another aspect of the present invention provides a precursor includingthe compound represented by Chemical Formula 1.

Still another aspect of the present invention provides a thin filmformed through deposition of the precursor including the compoundrepresented by Chemical Formula 1.

Yet another aspect of the present invention provides a method ofmanufacturing a thin film, including introducing the precursor includingthe compound represented by Chemical Formula 1 into a reactor.

According to the present invention, a novel heteroleptic precursorcompound, composed of a transition metal of Group 12 (Zn: zinc) or Group13 (Al: aluminum; Ga: gallium; In: indium) and an alkyl group(s) and analkoxy amide group, can be prepared. The Al precursor compound has athin film deposition rate comparable to existing TMA(trimethylaluminum), can be used as an alternative to TMA(trimethylaluminum), which is pyrophoric under atmospheric conditions,and has a wide processing temperature range (ALD window).

Also, the precursor compound has thermal stability that preventsdecomposition upon vaporization, high reactivity with a variety ofoxidizing agents, and a wide processing temperature range (ALD window).Moreover, a stoichiometric metal oxide thin film having high purity canbe obtained, and superior step coverage can be exhibited.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a graph showing the results of thermogravimetric analysis(TGA) of the properties of novel precursor compounds according to thepresent invention;

FIG. 2 is a graph showing changes in the thin film deposition ratedepending on the precursor injection time in the atomic layer depositionprocess of the compound of Comparative Example 1 and the compound ofExample 1 using ozone (O₃) as an oxidizing agent in Preparation Example1, in which the thin film deposition rate is uniform;

FIG. 3 is a graph showing changes in the thin film deposition ratedepending on the processing temperature in the atomic layer depositionprocess of the compound of Comparative Example 1 and the compound ofExample 1 using ozone (O₃) as an oxidizing agent in Preparation Example1, in which a stable thin film deposition rate depending on thetemperature and thus a wide processing temperature range (ALD window)are exhibited in Example 1;

FIG. 4 is a graph showing the results of X-ray photoelectronspectroscopy (XPS) of the component content of the Al₂O₃ thin filmresulting from atomic layer deposition (ALD) of the compound of Example1, in the atomic layer deposition process of the compound of ComparativeExample 1 and the compound of Example 1 using ozone (O₃) as an oxidizingagent in Preparation Example 1;

FIG. 5 is a graph showing changes in the thin film deposition ratedepending on the precursor injection time in the atomic layer depositionprocess of the compound of Comparative Example 1 and the compound ofExample 1 using water (H₂O) as an oxidizing agent in Preparation Example2, in which the thin film deposition rate is uniform;

FIG. 6 is a graph showing changes in the thin film deposition ratedepending on the processing temperature in the atomic layer depositionprocess of the compound of Comparative Example 1 and the compound ofExample 1 using water (H₂O) as an oxidizing agent in Preparation Example2, in which a stable thin film deposition rate depending on theprocessing temperature and thus a wide processing temperature range (ALDwindow) are exhibited in Example 1;

FIG. 7 is a graph showing the results of XPS of the component content ofthe Al₂O₃ thin film resulting from atomic layer deposition (ALD) of thecompound of Example 1, in the atomic layer deposition process of thecompound of Comparative Example 1 and the compound of Example 1 usingwater (H₂O) as an oxidizing agent in Preparation Example 2;

FIG. 8 is a graph showing the thickness of the Al₂O₃ thin film dependingon the deposition cycles in the atomic layer deposition process of thecompound of Example 1 using water (H₂O) as an oxidizing agent inPreparation Example 2;

FIG. 9 is a graph showing the Al₂O₃ thin film deposition rate and thedensity depending on the temperature in the atomic layer depositionprocess of the compound of Example 1 using water (H₂O) as an oxidizingagent in Preparation Example 2; and

FIG. 10 is transmission electron microscopy (TEM) images showing theresults of step coverage in the atomic layer deposition process of thecompound of Example 1 using water (H₂O) as an oxidizing agent inPreparation Example 2, in which the processing temperature is 150° C. or300° C., showing the hole structure and the trench structure, the aspectratio (AR) of the hole structure being 26:1 and the aspect ratio of thetrench structure being 40:1.

DESCRIPTION OF SPECIFIC EMBODIMENTS

Hereinafter, a detailed description will be given of embodiments of thepresent invention, which may be easily performed by those skilled in theart to which the present invention belongs. However, the presentinvention may be embodied in a variety of different forms, and is notlimited to the embodiments herein.

An aspect of the present invention pertains to a compound represented byChemical Formula 1 below.

In Chemical Formula 1, when M is a divalent transition metal of Group 12on the periodic table, n is 1; when M is a trivalent transition metal ofGroup 13 on the periodic table, n is 2; and R₁ to R₅ are hydrogen, asubstituted or unsubstituted C1 to C4 linear or branched alkyl group, oran isomer thereof.

In an embodiment of the present invention, M in Chemical Formula 1 mayinclude, but is not limited to, any one selected from the groupconsisting of Al, Zn, In and Ga.

In an embodiment of the present invention, R₁ to R₅ in Chemical Formula1 may include, but are not limited to, any one selected from the groupconsisting of hydrogen, a methyl group, an ethyl group, an n-propylgroup, an iso-propyl group, an n-butyl group, an iso-butyl group, asec-butyl group, a tert-butyl group and isomers thereof.

In the above compound, M and R₁ to R₅ may be at least one selected fromthe group consisting of combinations of the above-listed examples, butare not limited thereto.

In an embodiment of the present invention, the precursor compound ofChemical Formula 1 may be a solid or a liquid at room temperature, andalso has high volatility and thermal stability, high reactivity withvarious oxidizing agents, and a wide processing temperature range (ALDwindow) in an ALD process.

In an embodiment of the present invention, the compound of ChemicalFormula 1 may be used as an alternative to an existing commerciallyavailable pyrophoric compound. The existing commercially availablecompound is composed exclusively of a transition metal and a homolepticalkyl group, and specific examples thereof may include AlMe₃, AlEt₃,ZnMe₂, ZnEt₂, GaMe₃, GaEt₃, InMe₃, and InEt₃ (Me: methyl, Et: ethyl).

The thin film deposition process includes an atomic layer deposition(ALD) process and a chemical vapor deposition (CVD) process.

The atomic layer deposition process is a technique for forming a thinfilm through a self-limiting reaction by alternately feeding elementsfor use in forming a thin film. The atomic layer deposition process isable to deposit a very thin film and to precisely control the desiredthickness and composition. This process enables the formation of a filmhaving a uniform thickness on a large-area substrate, and exhibitssuperior step coverage even at a high aspect ratio. Furthermore, thethin film contains small amounts of impurities.

The chemical vapor deposition process is a technique for forming adesired thin film on the surface of a substrate by applying appropriateactivity and reactive energy through injection of reactive gas into areactor. This process enables mass production, is cost-effective, makesit possible to deposit various kinds of elements and compounds, andmakes it easy to obtain a thin film having various properties by virtueof wide processing control ranges, and moreover realizes superior stepcoverage.

In an embodiment of the present invention, a precursor composition foruse in the atomic layer deposition (ALD) and the chemical vapordeposition (CVD) includes a compound represented by Chemical Formula 1below.

In an embodiment of the present invention, M in Chemical Formula 1 maybe a transition metal of Groups 12 and 13 on the periodic table, andpreferably M is any one selected from the group consisting of Al, Zn, Inand Ga, but is not limited thereto.

In an embodiment of the present invention, R₁ to R₅ in Chemical Formula1 may be any one selected from the group consisting of hydrogen, amethyl group, an ethyl group, an n-propyl group, an iso-propyl group, ann-butyl group, an iso-butyl group, a sec-butyl group, a tert-butyl groupand isomers thereof. Preferable is a compound in which R₁ is a methylgroup, R₂ and R₃ are hydrogen or a methyl group, R₄ is a tert-butylgroup, and R₅ is a methyl group or an ethyl group. More preferable isany one selected from the group consisting ofAl(CH₃)₂[CH₃OC(CH₃)₂CH₂NtBu], Al(CH₃)₂[CH₃OCH(CH₃)CH₂NtBu],Al(CH₃)₂[CH₃OCH₂CH₂NtBu], Zn(CH₃)[CH₃OCH₂CH₂NtBu],Zn(CH₃)[CH₃OC(CH₃)₂CH₂NtBu], Zn(Et)[CH₃OC(CH₃)₂CH₂NtBu],In(CH₃)₂[CH₃OCH₂CH₂NtBu], and Ga(CH₃)₂[CH₃OCH₂CH₂NtBu] (Et: ethyl, tBu:tert-butyl), but the present invention is not limited thereto.

Another aspect of the present invention pertains to a precursorincluding the compound represented by Chemical Formula 1.

Still another aspect of the present invention pertains to a thin filmformed by depositing the precursor including the compound represented byChemical Formula 1.

Yet another aspect of the present invention pertains to a method ofmanufacturing a thin film, including introducing a precursor includingthe compound represented by Chemical Formula 1 into a reactor. Also, themethod of manufacturing a thin film according to the present inventionprovides a method of manufacturing an oxide film, a nitride film, or ametal film using an oxidizing agent, a nitriding agent or a reducingagent.

In an embodiment of the present invention, the ALD processingtemperature falls in the range of 80° C. to 400° C., but is not limitedthereto, and the preferable processing temperature falls in the range of130° C. to 320° C.

In an embodiment of the present invention, the injection time of theprecursor compound may fall in the range of 0.2 sec to 10 sec, but isnot limited thereto, and the preferable injection time is 2 to 10 sec inan 03 process and 1 to 5 sec in a H₂O process.

In an embodiment of the present invention, the oxidizing agent is ozone(O₃) or water (H₂O), but is not limited thereto.

A better understanding of the present invention will be given throughthe following examples, which are merely set forth to illustrate thepresent invention but are not to be construed as limiting the presentinvention.

A typical synthesis process of the present embodiment is represented inScheme 1 below.

Here, the synthesis process when M (transition metal) is Al (aluminum)is represented in Scheme 2 below.

[Example 1] Preparation of Al(CH₃)₂[CH₃OC(CH₃)₂CH₂NtBu]

1 equivalent of a ligand CH₃OC(CH₃)₂CH₂NHtBu was added to 1 equivalentof 2M Al(Me)₃, dissolved in hexane or heptane at −78° C., after whichthe temperature was slowly elevated to room temperature and stirring wasperformed for about 16 hr. The reaction was completed and the solventwas removed in a vacuum. The compound thus obtained was subjected tovacuum distillation, thereby yielding a colorless liquid precursorAl(CH₃)₂[CH₃OC(CH₃)₂CH₂NtBu]. ¹H NMR (C₆D₆): δ 2.75(Al(CH₃)₂[CH₃OC(CH₃)₂CH₂NtBu], s, 2H), 2.63(Al(CH₃)₂[CH₃OC(CH₃)₂CH₂NtBu], s, 3H), 1.28Al(CH₃)₂[CH₃OC(CH₃)₂CH₂NtBu], s, 9H), 0.83(Al(CH₃)₂[CH₃OC(CH₃)₂CH₂NtBu], s, 6H), −0.43(Al(CH₃)₂[CH₃OC(CH₃)₂CH₂NtBu], s, 6H).

[Example 2] Preparation of Al(CH₃)₂[CH₃OCH(CH₃)CH₂NtBu]

1 equivalent of a ligand CH₃OCH(CH₃)CH₂NHtBu was added to 1 equivalentof 2M Al(Me)₃, dissolved in hexane or heptane at −78° C., after whichthe temperature was slowly elevated to room temperature and stirring wasperformed for about 16 hr. The reaction was completed and the solventwas removed in a vacuum. The compound thus obtained was subjected tovacuum distillation, thereby yielding a colorless liquid precursorAl(CH₃)₂[CH₃OCH(CH₃)CH₂NtBu]. ¹H NMR (C₆D₆): δ 3.40-3.32(Al(CH₃)₂[CH₃OCH(CH₃)CH₂NtBu], m, 1H), 2.88(Al(CH₃)₂[CH₃OCH(CH₃)CH₂NtBu], dd, J, =11.1 Hz, J₂=4.7 Hz, 1H),2.69-2.65 (Al(CH₃)₂[CH₃OCH(CH₃)CH₂NtBu], m, 1H), 2.66(Al(CH₃)₂[CH₃OCH(CH₃)CH₂NtBu], s, 3H), 1.29(Al(CH₃)₂[CH₃OCH(CH₃)CH₂NtBu], s, 9H), 0.68(Al(CH₃)₂[CH₃OCH(CH₃)CH₂NtBu], d, J=5.8 Hz, 3H), −0.40(Al(CH₃)₂[CH₃OCH(CH₃)CH₂NtBu], s, 3H), −0.44(Al(CH₃)₂[CH₃OCH(CH₃)CH₂NtBu], s, 3H).

[Example 3] Preparation of Al(CH₃)₂[CH₃OCH₂CH₂NtBu]

1 equivalent of a ligand CH₃OCH₂CH₂NHtBu was added to 1 equivalent of 2MAl(Me)₃ dissolved in hexane or heptane at −78° C., after which thetemperature was slowly elevated to room temperature and stirring wasperformed for about 16 hr. The reaction was completed and the solventwas removed in a vacuum. The compound thus obtained was subjected tovacuum distillation, thereby yielding a colorless liquid precursorAl(CH₃)₂[CH₃OCH₂CH₂NtBu]. ¹H NMR (C₆D₆): δ 3.09(Al(CH₃)₂[CH₃OCH₂CH₂NtBu], t, J=6.9 Hz, 2H), 2.79(Al(CH₃)₂[CH₃OCH₂CH₂NtBu], t, J=6.9 Hz, 2H), 2.62(Al(CH₃)₂[CH₃OCH₂CH₂NtBu], s, 3H), 1.28 (Al(CH₃)₂[CH₃OCH₂CH₂NtBu], s,9H), −0.44 (Al(CH₃)₂[CH₃OCH₂CH₂NtBu], s, 6H).

Here, the synthesis process when M (transition metal) is Zn (zinc) isrepresented in Scheme 3 below.

[Example 4] Preparation of Zn(CH₃)[CH₃OCH₂CH₂NtBu]

1 equivalent of a ligand CH₃OCH₂CH₂NHtBu was added to 1 equivalent of1.2M Zn(Me)₂ dissolved in toluene at −78° C., after which thetemperature was slowly elevated to room temperature and stirring wasperformed for about 16 hr. The reaction was completed and the solventwas removed in a vacuum. The compound thus obtained was subjected tovacuum distillation, thereby yielding a white solid precursorZn(CH₃)[CH₃OCH₂CH₂NtBu]. ¹H NMR (C₆D₆): δ 3.01-2.96(Zn(CH₃)[CH₃OCH₂CH₂NtBu], m, 2H), 2.99 (Zn(CH₃)[CH₃OCH₂CH₂NtBu], s, 3H),2.33-2.29 (Zn(CH₃)[CH₃OCH₂CH₂NtBu], m, 2H), 0.91(Zn(CH₃)[CH₃OCH₂CH₂NtBu], s, 9H), −0.39 (Zn(CH₃)[CH₃OCH₂CH₂NtBu], s, 3H)

Here, the synthesis process when M (transition metal) is In (indium) isrepresented in Scheme 4 below.

[Example 5] Preparation of In(CH₃)₂[CH₃OCH₂CH₂NtBu]

1 equivalent of a ligand CH₃OCH₂CH₂NHtBu was added to 1 equivalent ofIn(Me)₃.EtO₂ dissolved in toluene at −78° C., after which thetemperature was slowly elevated to room temperature and heating to 110°C. was performed for about 16 hr. The reaction was completed and thesolvent was removed in a vacuum. The compound thus obtained wassubjected to vacuum distillation, thereby yielding a colorless liquidprecursor In(CH₃)₂[CH₃OCH₂CH₂NtBu]. ¹H NMR (C₆D₆): δ 3.21(In(CH₃)₂[CH₃OCH₂CH₂NtBu], t, J=5.5 Hz, 2H), 2.99(In(CH₃)₂[CH₃OCH₂CH₂NtBu], s, 3H), 2.48-2.43 (In(CH₃)₂[CH₃OCH₂CH₂NtBu],m, 2H), 0.85 (In(CH₃)₂[CH₃OCH₂CH₂NtBu], s, 9H), 0.00 (In(CH₃)2[CH₃OCH₂CH₂NtBu], s, 6H).

Here, the synthesis process when M (transition metal) is Ga (gallium) isrepresented in Scheme 5 below.

[Example 6] Preparation of Ga(CH₃)₂[CH₃OCH₂CH₂NtBu]

1 equivalent of a ligand CH₃OCH₂CH₂NHtBu was added to 1 equivalent ofGa(Me)₃.EtO₂ dissolved in toluene at −78° C., after which thetemperature was slowly elevated to room temperature and heating to 110°C. was performed for about 16 hr. The reaction was completed and thesolvent was removed in a vacuum. The compound thus obtained wassubjected to vacuum distillation, thereby yielding a colorless liquidprecursor Ga(CH₃)₂[CH₃OCH₂CH₂NtBu]. ¹H NMR (C₆D₆): δ 3.21(Ga(CH₃)₂[CH₃OCH₂CH₂NtBu], t, J=5.2 Hz, 2H), 3.00(Ga(CH₃)₂[CH₃OCH₂CH₂NtBu], s, 3H), 2.55-2.51 (Ga(CH₃)₂[CH₃₀ CH₂CH₂NtBu],m, 2H), 0.92 (Ga(CH₃)₂[CH₃OCH₂CH₂NtBu], s, 9H), 0.00(Ga(CH₃)₂[CH₃OCH₂CH₂NtBu], s, 6H).

Also, Zn(CH₃)[CH₃OC(CH₃)₂CH₂NtBu] in [Example 7] andZn(Et)[CH₃OC(CH₃)₂CH₂NtBu] in [Example 8] were synthesized using thereaction of Scheme 3.

The structural formulas of the synthesized precursors of Examples andComparative Example are shown in Table 1 below.

TABLE 1 Precursor Structural Formula Example 1Al(CH₃)₂[CH₃OC(CH₃)₂CH₂NtBu] (tBu: tert-Bu)

Example 2 Al(CH₃)₂[CH₂OCH(CH₃)CH₂NtBu]

Example 3 Al(CH₃)₂[CH₃OCH₂CH₂NtBu]

Example 4 Zn(CH₃)[CH₃OCH₂CH₂NtBu]

Example 5 In(CH₃)₂[CH₃OCH₂CH₂NtBu]

Example 6 Ga(CH₃)₂[CH₃OCH₂CH₂NtBu]

Example 7 Zn(CH₃)[CH₃OC(CH₃)₂CH₂NtBu]

Example 8 Zn(Et)[CH₃OC(CH₃)₂CH₂NtBu] (Et: ethyl)

Comparative Example 1 TMA [trimethylaluminum]

[Test Example 1] Measurement of Properties of Precursor Compounds

The properties of Al(CH₃)₂ [CH₃OC(CH₃)₂CH₂NtBu],Al(CH₃)₂[CH₃OCH(CH₃)CH₂NtBu] and Al(CH₃)₂[CH₃OCH₂CH₂NtBu] precursorcompounds of Examples were measured. Here, the properties of interestwere the state at room temperature (RT), the boiling point, andpyrophoric ignition.

The measured values of the above properties are shown in Table 2 below.

TABLE 2 Test Example 1 State Boiling point Reactivity in Precursor (RT)(based on bath) atmosphere Example 1 Al(CH₃)₂[CH₃OC(CH₃)₂CH₂NtBu] Liquid50° C. @0.3 Torr Nonpyrophoric Example 2 Al(CH₃)₂[CH₃OCH(CH₃)CH₂NtBu]Liquid 50° C. @0.3 Torr Nonpyrophoric Example 3 Al(CH₃)₂[CH₃OCH₂CH₂NtBu]Liquid 45° C. @0.5 Torr Nonpyrophoric Example 4 Zn(CH₃)[CH₃OCH₂CH₂NtBu]Solid Sublimation point: Nonpyrophoric 35° C. @0.3 Torr Example 5In(CH₃)₂[CH₃OCH₂CH₂NtBu] Liquid 60° C. @0.7 Torr Nonpyrophoric Example 6Ga(CH₃)₂[CH₃OCH₂CH₂NtBu] Liquid 60° C. @0.7 Torr NonpyrophoricComparative TMA Liquid 125° C. Pyrophoric Example 1

As is apparent from Table 2, Examples 1 to 6 of the present inventionare nonpyrophoric under atmospheric conditions, and are a solid or aliquid at room temperature.

[Test Example 2] Thermogravimetric Analysis (TGA) of Precursor Compounds

The precursor compounds of Example 1 (Al(CH₃)₂[CH₃OC(CH₃)₂CH₂NtBu]),Example 2 (Al(CH₃)₂[CH₃OCH(CH₃)CH₂NtBu]) and Example 3(Al(CH₃)₂[CH₃OCH₂CH₂NtBu]) were subjected to TGA.

Upon TGA, a TGA/DSC 1 STAR′ System available from Mettler Toledo wasused as an instrument, and 50 μL of an alumina crucible was used. Theamounts of all samples were 10 mg, and measurement was performed in thetemperature range of 30° C. to 400° C. The specific conditions andmeasured values for TGA are shown in Table 3 below and in FIG. 1.

TABLE 3 Test Example 2 Precursor Example 1 Example 2 Example 3 T_(1/2)(° C.) 155 150 132 Residual amount at 300° C. 0.1% 0.6% 0.8%

As is apparent from Table 3, the half-weight loss temperature [T½ (′C)]of the precursors of Examples 1 to 3 is 132° C. to 155° C. Also, theresidual amount is almost zero at 300° C., and thermal stability isexhibited without decomposition upon vaporization.

[Preparation Example] Evaluation of Film Formation Through Atomic LayerDeposition (ALD) of Precursor Compound

The precursor compound of Example 1 (Al(CH₃)₂[CH₃OC(CH₃)₂CH₂NtBu]) wasevaluated for film formation through atomic layer deposition (ALD). Asoxidizing agents, ozone (O₃) and water (H₂O) were used, and argon (Ar)or nitrogen (N₂) inert gas was used for purging. The injection of theprecursor, argon, ozone or water and argon was set as one cycle, anddeposition was performed on a silicon (Si) wafer.

As the film formation evaluation items of the thin film manufactured inPreparation Example 1, when ozone (O₃) was used as the oxidizing agentduring the processing of the precursor compound of Example 1(Al(CH₃)₂[CH₃OC(CH₃)₂CH₂NtBu]), changes in the thin film deposition ratedepending on the injection time of the precursor, changes in the thinfilm deposition rate depending on the processing temperature, and theamounts of aluminum (Al), oxygen (O), and carbon (C) in the depositedthin film and the O/Al ratio through XPS (X-ray photoelectronspectroscopy) were measured.

As the film formation evaluation items of the thin film manufactured inPreparation Example 2, when water (H₂O) was used as the oxidizing agentduring the processing of the precursor compound of Example 1(Al(CH₃)₂[CH₃OC(CH₃)₂CH₂NtBu]), changes in the thin film deposition ratedepending on the injection time of the precursor, changes in the thinfilm deposition rate depending on the processing temperature, theamounts of aluminum (Al), oxygen (O), and carbon (C) in the depositedthin film and the O/Al ratio through XPS (X-ray photoelectronspectroscopy), changes in the thickness of the thin film depending onthe deposition cycles (growth linearity), the density of Al₂O₃ dependingon the temperature, and step coverage were measured.

[Preparation Example 1] Evaluation of Film Formation Through AtomicLayer Deposition of Precursor of Example 1 Using 03 as Oxidizing Agent

<Changes in Thin Film Deposition Rate Depending on Precursor InjectionTime (Saturation)>

Upon atomic layer deposition (ALD) of the precursor of Example 1(Al(CH₃)₂[CH₃OC(CH₃)₂CH₂NtBu]) using ozone (O₃), the injection time ofthe precursor compound, exhibiting a uniform thin film deposition rate,was measured, and thus a self-limiting reaction was confirmed.

As shown in FIG. 2, the uniform thin film deposition rate was obtainedafter an injection time of 1 sec when the processing temperature of theprecursor of Comparative Example 1 (TMA) was 300° C., and was obtainedafter an injection time of 4 sec when the processing temperature of theprecursor of Example 1 was 260° C.

TABLE 4 Carrier gas Purging gas Precursor O₃ Precursor injection O₃Processing injection Injection Purging gas injection Purging gas Temp.amount Concent. Temp. amount time injection time time injection timeProcesses Precursor (° C.) (sccm) (g/m³) (° C.) (sccm) (sec) (sec) (sec)(sec) (cycles) Ex.1 40 5 144 260 100   2~10 10 3 10 200 C.Ex.1 5 10 144300 500 0.2~2 10 1.2 10 200

As is apparent from Table 4, in Example 1, a precursor (2 to 10 sec), Ar(10 sec), 03 (3 sec), and Ar (10 sec) were sequentially fed, and theflow rate of argon (Ar) for purging the precursor was set to 100 sccm.The reactive gas ozone (O₃) was injected at a concentration of 144 g/m³.The temperature of the precursor was 40° C., the flow rate of thecarrier gas was 5 sccm, the processing temperature was 260° C., and thenumber of process cycles was 200.

In Comparative Example 1, a precursor (0.2 to 2 sec), Ar (10 sec), 03(1.2 sec), and Ar (10 sec) were sequentially fed, and the flow rate ofargon (Ar) for purging the precursor was set to 500 sccm. The reactivegas ozone was injected at a concentration of 144 g/m³. The temperatureof the precursor of Comparative Example 1 was 5° C., the flow rate ofthe carrier gas was 10 sccm, the processing temperature was 300° C., andthe number of process cycles was 200.

<Changes in Thin Film Deposition Rate Depending on ProcessingTemperature (ALD Window)>

Upon atomic layer deposition (ALD) of the precursor of Example 1(Al(CH₃)₂[CH₃OC(CH₃)₂CH₂NtBu]) using ozone (O₃), the thin filmdeposition rate at different temperatures was measured, and thus theprocessing temperature range (ALD window) was confirmed. As shown inFIG. 3, the precursor of Example 1 exhibited a uniform thin filmdeposition rate in a processing temperature range (ALD window) of 150°C. to 320° C.

TABLE 5 Carrier gas Purging gas Precursor O₃ Precursor injection O₃Processing injection Injection Purging gas injection Purging gas Temp.amount Concent. Temp. amount time injection time time injection timeProcesses Precursor (° C.) (sccm) (g/m³) (° C.) (sccm) (sec) (sec) (sec)(sec) (Cycles) Ex.1 40 5 144 150~320 100 5 10 3 10 200 C.Ex.1 5 10 144130~320 500 1 10 1.2 10 200

As is apparent from Table 5, the processing temperature range (ALDwindow) of the precursor of Example 1 was wide to an extent comparableto that of the commercially available precursor (TMA) of ComparativeExample 1.

<Element Content in Al₂O₃ Thin Film and O/Al Ratio>

Upon atomic layer deposition (ALD) of the precursor of Example 1(Al(CH₃)₂[CH₃OC(CH₃)₂CH₂NtBu]) using ozone (O₃), the element content(atomic %) and the element ratio (atomic ratio, O/Al) depending on theprocessing temperature were measured through XPS (X-ray photoelectronspectroscopy).

As seen in FIG. 4, the processing temperature fell in the range of 80°C. to 300° C. and the amount of the stoichiometric Al₂O₃ thin filmdepending on the temperature was determined.

TABLE 6 Preparation Example 1 Temperature Example 1(Al(CH₃)₂[CH₃OC(CH₃)₂CH₂NtBu] + O₃ (° C.) Al (%) O (%) C (%) O/Al Ratio80 38.91 61.09 — 1.57 200 41.54 58.46 — 1.41 300 42.33 57.67 — 1.36

As is apparent from Table 6, no carbon (C) was observed, even at a lowtemperature. As the temperature was elevated, the amount of Al(aluminum) was increased and the amount of O (oxygen) was decreased, andthus the O/Al ratio was reduced.

[Preparation Example 2] Evaluation of Film Formation Through AtomicLayer Deposition of Precursor of Example 1 Using H₂O as Oxidizing Agent

<Changes in Thin Film Deposition Rate Depending on Precursor InjectionTime (Saturation)>

Upon atomic layer deposition (ALD) of the precursor of Example 1(Al(CH₃)₂[CH₃OC(CH₃)₂CH₂NtBu]) using water (H₂O), the injection time ofthe precursor compound, exhibiting the uniform thin film depositionrate, was measured, and thus a self-limiting reaction was confirmed. Asshown in FIG. 5, a uniform thin film deposition rate was obtained afteran injection time of the precursor (TMA) of Comparative Example 1 of 1sec when the processing temperature was 150° C.

TABLE 7 Carrier Gas Purging Gas Precursor H₂O Precursor Injection H₂OProcessing Injection Injection Purging Gas Injection Purging Gas Temp.Amount Temp. Temp. Amount Time Injection Time Time Injection TimeProcesses Precursor (° C.) (sccm) (° C.) (° C.) (sccm) (sec) (sec) (sec)(sec) (Cycles) Ex.1 40 10 10 150 100  1-5 20 1.2 20 200 C.Ex.1 5 10 10150 500 0.2-2 10 1.2 10 200

As is apparent from Table 7, in Example 1, the precursor (1 to 5 sec),Ar (20 sec), H₂O (1.2 sec), and Ar (20 sec) were sequentially fed, andthe flow rate of argon (Ar) for purging the precursor was set to 100sccm. The temperature of the precursor of Example 1 was 40° C., the flowrate of the carrier gas was 10 sccm, the temperature of water, servingas the oxidizing agent, was 10° C., the processing temperature was 150°C., and the number of process cycles was 200.

In Comparative Example 1, the precursor (0.2 to 2 sec), Ar (10 sec), H₂O(1.2 sec), and Ar (10 sec) were sequentially fed, and the flow rate ofargon (Ar) for purging the precursor was set to 500 sccm. Thetemperature of the precursor of Comparative Example 1 was 5° C., theflow rate of the carrier gas was 10 sccm, the temperature of water,serving as the oxidizing agent, was 10° C., the processing temperaturewas 150° C., and the number of process cycles was 200.

<Changes in Thin Film Deposition Rate Depending on ProcessingTemperature (ALD Window)>

Upon atomic layer deposition (ALD) of the precursor of Example 1(Al(CH₃)₂[CH₃OC(CH₃)₂CH₂NtBu]) using water (H₂O), the thin filmdeposition rate at different temperatures was measured and thus theprocessing temperature range (ALD window) was confirmed. As shown inFIG. 6, the precursor of Example 1 exhibited a uniform thin filmdeposition rate in the processing temperature range (ALD window) of 130°C. to 320° C. The precursor of Comparative Example 1 showed a uniformthin film deposition rate in the range of 130° C. to 200° C., but thethin film deposition rate was lowered in the range of 200° C. to 320° C.As is apparent from Table 8 below and the above description, theprocessing temperature range (ALD window) was wider in the precursor ofExample 1 than in the precursor of Comparative Example 1.

TABLE 8 Carrier gas Purging gas Precursor H₂O Precursor injection H₂OProcessing injection Injection Purging gas injection Purging gas Temp.amount Temp. Temp. amount time injection time time injection timeProcesses Precursor (° C.) (sccm) (° C.) (° C.) (sccm) (sec) (sec) (sec)(sec) (Cycles) Ex.1 40 10 10 130-320 100 5 20 1.2 20 200 C.Ex.1 5 10 10130-320 500 1 10 1.2 10 200

As is apparent from Table 8 and the above description, the precursor ofExample 1 had a wider processing temperature range (ALD window) than thecommercially available precursor (TMA) of Comparative Example 1.Furthermore, upon measurement of the processing temperature range, inthe precursor of Comparative Example 1, the amount of the purging gasthat was injected was five times that of Example 1, the injection timeof the precursor was one fifth as long thereof, and the injection timeof the purging gas was half thereof.

<Element Content in Al₂O₃ Thin Film and O/Al Ratio>

Upon atomic layer deposition (ALD) of the precursor of Example 1(Al(CH₃)₂[CH₃OC(CH₃)₂CH₂NtBu]) using water (H₂O), the element content(atomic %) and the element ratio (atomic ratio, O/Al) depending on theprocessing temperature were measured through XPS (X-ray photoelectronspectroscopy).

As seen in FIG. 7, the processing temperature fell in the range of 150°C. to 300° C., and the amount of stoichiometric Al₂O₃ thin film wasdetermined depending on the temperature.

TABLE 9 Preparation Example 2 Temperature Example 1(Al(CH₃)₂[CH₃OC(CH₃)₂CH₂NtBu]) + H₂O (° C.) Al (%) O (%) C (%) O/Alratio 150 37.93 59.36 1.93 1.57 300 38.7 60.3 0.99 1.56

As is apparent from Table 9, the amounts of Al (aluminum) and O (oxygen)and the O/Al ratios were similar at temperatures of 150° C. and 300° C.

<Changes in Thickness of Thin Film Depending on Process Cycles (GrowthLinearity)>

Upon atomic layer deposition (ALD) of the precursor of Example 1(Al(CH₃)₂[CH₃OC(CH₃)₂CH₂NtBu]) using water (H₂O), changes in thethickness of the thin film depending on the deposition cycles weresimilar at temperatures of 150° C. and 300° C. FIG. 8 is a graph showingchanges in the thickness of the thin film depending on the processcycles, showing that the thin film deposition rate was 0.91 Å/cycle at150° C. and 0.93 Å/cycle at 300° C.

<Density of Al₂O₃ Thin Film at Different Temperatures (Film Density byXRR)>

Upon atomic layer deposition (ALD) of the precursor of Example 1(Al(CH₃)₂[CH₃OC(CH₃)₂CH₂NtBu]) using water (H₂O), the density of thethin film depending on the processing temperature was found to increasewith an elevation in the temperature, and the density of the thin filmwas higher when using the precursor of Example 1 than when using theprecursor of Comparative Example 1, which is apparent from FIG. 9 andTable 10 below. Table 10 below shows the density of Al₂O₃(Bulk) and thedensity depending on the temperature upon atomic layer deposition of theprecursor (TMA) of Comparative Example 1 using water (H₂O), inconnection with which reference may be made to Chem. Mater. 2004, 16,639.

TABLE 10 Al₂O₃ Density Bulk 3.70-3.80 g/cm³ Example 3.20 g/cm³ (150° C.)3.60 g/cm³ (300° C.) Comparative Example 1 2.46 g/cm³ (33° C.) 3.06g/cm³ (177° C.)

<Step Coverage of Al₂O₃ Thin Film at Different Temperatures (StepCoverage by TEM)>

Upon atomic layer deposition (ALD) of the precursor of Example 1(Al(CH₃)₂[CH₃OC(CH₃)₂CH₂NtBu]) using water (H₂O), the step coverage ofthe hole and trench structures depending on the temperature was observedthrough TEM (Transmission Electron Microscopy). The processingtemperatures were 150° C. and 300° C., and the aspect ratio (AR) was26:1 in the hole structure and 40:1 in the trench structure.

TABLE 11 Hole structure Trench structure [AR 26:1] [AR 40:1] 150° C.300° C. 150° C. 300° C. Top thickness 21.57 nm 21.41 nm 20.92 nm 22.82nm Side thickness 22.18 nm 22.42 nm 21.45 nm 22.80 nm Bottom thickness21.13 nm 20.89 nm 20.64 nm 22.50 nm Bottom step coverage  97.9%  97.5% 98.6% 98.6% Side step coverage 102.8% 104.7% 102.5% 99.9%

As is apparent from Table 11, the step coverage in the hole and trenchstructures was 98% or more at 150° C. and 300° C. Thus, the precursor ofExample 1 exhibited superior step coverage in a wide temperature range.

Although embodiments of the present invention have been described, thoseskilled in the art will appreciate that the present invention may beembodied in other specific forms without changing the technical spiritor essential features thereof. Thus, the embodiments described aboveshould be understood to be non-limiting and illustrative in every way.

The scope of the present invention is represented by the followingclaims, rather than the detailed description, and it is to be understoodthat the meaning and scope of the claims and all variations or modifiedforms derived from equivalent concepts thereof fall within the scope ofthe present invention.

What is claimed is:
 1. A compound represented by Chemical Formula 1below:

in Chemical Formula 1, when M is a divalent transition metal of Group 12on a periodic table, n is 1; when M is a trivalent transition metal ofGroup 13 on a periodic table, n is 2; and R₁ to R₅ are hydrogen, asubstituted or unsubstituted C₁ to C₄ linear or branched alkyl group oran isomer thereof.
 2. The compound of claim 1, wherein the M in ChemicalFormula 1 is any one selected from the group consisting of Al, Zn, Inand Ga.
 3. The compound of claim 1, wherein the R₁ to R₅ in ChemicalFormula 1 are any one selected from the group consisting of hydrogen, amethyl group, an ethyl group, an n-propyl group, an iso-propyl group, ann-butyl group, an iso-butyl group, a sec-butyl group, a tert-butyl groupand an isomer thereof.
 4. The compound of claim 1, wherein the R₁ is amethyl group; the R₂ and R₃ are hydrogen or a methyl group; the R₄ is atert-butyl group; and the R₅ is a methyl group or an ethyl group.
 5. Thecompound of claim 1, wherein the Chemical Formula 1 is any one selectedfrom the group consisting of Al(CH₃)₂[CH₃OC(CH₃)₂CH₂NtBu],Al(CH₃)₂[CH₃OCH(CH₃)CH₂NtBu], Al(CH₃)₂[CH₃OCH₂CH₂NtBu],Zn(CH₃)[CH₃OCH₂CH₂NtBu], Zn(CH₃)[CH₃OC(CH₃)₂CH₂NtBu],Zn(Et)[CH₃OC(CH₃)₂CH₂NtBu], In(CH₃)₂[CH₃OCH₂CH₂NtBu], andGa(CH₃)₂[CH₃OCH₂CH₂NtBu] (wherein Et is ethyl, and tBu is a tert-butylgroup).
 6. A precursor comprising the compound of any one of claims 1 to5.
 7. A method of manufacturing a thin film, comprising introducing aprecursor comprising the compound of any one of claims 1 to 5 into areactor.
 8. The method of claim 7, wherein the method includes atomiclayer deposition (ALD) or chemical vapor deposition (CVD).
 9. The methodof claim 7, wherein the method includes using at least one selected fromthe group consisting of an oxidizing agent, a nitriding agent and areducing agent.
 10. The method of claim 7, wherein the thin filmincludes an oxide film, a nitride film or a metal film.